My initial reaction to the SD9 was pretty positive. Now that I've had more time to work with it though, some of my enthusiasm for it has waned. In particular, it has obvious issues with its autofocus, and I found its exposure metering to be problematic as well. It's white balance also struck me as less effective than that of its competition, and the camera's maximum 400 ISO and limited maximum exposure times further restrict its utility.

The SD9's X3 sensor does indeed deliver more resolution per pixel than conventional striped sensor arrays, but it still doesn't resolve quite as much detail as the six-megapixel competition. Its images are very sharp, but that's at least partially because it has no antialiasing filter. Thus, while it is pretty completely immune to color aliasing, it is much more subject to luminance aliasing than its competition. It's possible that including an aliasing filter in the design would indeed show the X3 sensor delivering 2x the resolution per pixel of conventional arrays, but as it is the strong luminance aliasing obscures the finest detail.

The combination of full-color pixels and lack of an antialiasing filter clearly produces images with a different "look" to them though, so there will doubtless be shooters who will prefer its images to those of other camera models. - Raw performance measurements rarely translate well into personal preferences.

The SD9's exposure flexibility is quite good, with all the modes and controls you'd expect to find on an SLR, although its 0.5 EV exposure adjustment steps are a little coarse for a digicam. Its combination of a RAW file format and the excellent Photo Pro software provides an excellent ability to adjust images post-capture, but at this point I have to say that the jury is still out as to whether the RAW files actually contain significant highlight detail beyond what appears in images converted to JPEG using the default settings.

The Sigma lenses that couple with the SD9 body do indeed appear to have very good optical characteristics, as well as very competitive prices in the marketplace. This could be viewed as a reason to buy the SD9, for those interested in accumulating a large collection of lenses on a budget. On the other hand, most of the same Sigma lenses are available for roughly the same prices with Nikon or Canon mounts, so anyone would be free to use them with one of the competing SLR designs if they wished.

I commented in the conclusion to my original "first look" at this camera that I expected something of a holy war to erupt on the 'net over the SD9's color rendition, resolution, and image noise, and that indeed has come to pass. It does appear though, that the images I and others have posted from the camera have injected a healthy level of reality into the discussions, and I hope that the test shots I've now posted, as well as the raw-format highlight headroom results (and eventually, some truly detailed noise measurements) will continue that trend.

As the first digital camera from a company not previously involved in the digital world at all, the SD9 is a remarkable achievement. It clearly has a number of limitations though, some of them serious. Taken as a whole, I think users give up an awful lot of capability for the roughly $400 in price that separates it from the competing models from Nikon and Canon (and the roughly $800 diference relative to Fuji's S2 Pro). I do think though, that the SD9 will nonetheless find happy homes with many shooters drawn by that price difference, and by the different "look" of the images produced by its full color pixels and non-antialiased optical design. Ultimately, the decision to purchase an SD9 will be a very personal one - I hope that the information I've presented here will help people make it in an informed fashion.